Electric heater



April 1o, 192s.

w. s. JOHNSON ET AL ELECTRIC HEATER Filed March 25, 1921 2 Sheets-Sheet l April l0, 1928. 1,665,367

w. s. JOHNSON ET A1.

ELECTRIC HEATER Patented Apr. l0, 1928.

'UNITED STATES pare-Nr sIGNoRs To AMERICAIN CARVAND CORPORATION or NEW JERSEY.

FOUNDRY COMPANY, 0F NEW YORK, N. Y., A.

ELECTRIC EATER.

Appncaun med Ieren 25, m21. serial No. 455,598'.

The accompanying drawings illustrate the preferred form of the invention, though it is to be understood that the invention is not limited to the exactv details of construction shown and described, as it is obvious that various modifications thereof Within the scope of the claims will occur to persons skilled in the art.

In said drawings: f

Figure 1 is,in part, a broken side eleva# tion of our improved electric heater and, in part, a section taken on the line 1 1 of Figure 2; i L

Figure 2 is, in part, an end elevation and, in part, a section taken on the line 2-2 of Figure 1; n

Figure 3 is, in part, an end elevation and, in part, a section taken on the line 3 3 of Figure 1; g

Figure 4 is a view, in section, shoivin'g an electrode Withdrawn to permit of the VWithdrawal of the Work piece from the heater; and

Figure 5 is a view, in section, showing the manner connecting the operating rods to the electrodes. n

It is an object of our invention to provide an improved electric heater adaptedto heat long bars such as are used in the making of rivets. It is also an object of our invention to provide an improved operating means for the electrodes of a heater of the type indicated andit is also an object oli our invention to provide an improved electrode for use in such a heater. c

In the embodiment of oiir inventionshown in the drawings, a plurality of chambered structures 1, of suitable refractory or heat insulating material, and. provided withk a plurality of chambers 2, are mounted on the channels 3 carried uponl a frame comprising the end members 4 and side member-s. The frame, in turn, is separated by insulation 6 from the side members 7 of' a truck having the journal boxes 8 that receive the axles 9 having the Wheels 10. The Wheels 10 travel upon rails 11 that are4 suitably supported upon opposite sides of the pit 12.

While we have shown three structures 1 mounted on the truck andeach structure having three chambers 2, fit will be understood that eachstructure mayhave a greater or a lesser number of chambers and that more orless structures maybe used'nd arranged on one or more trucks in order to provide sufficient chambers to heat bars at the desired rate.

The channels 3 are placed with their flanges 13 projecting upwardly forming troughs in which the structures 1 are placed. To the flanges 13 are riveted the angle pieces 14 provided with openings through ,which extend the Ibolts 15 that secure the Wooden cross-bars 16 in place. The cross-bars 16 securethe structures 1 to the channels3 and keep the angle bars 17 in place on the eX- posed edges of the structure.

At one end the Webs 18 of the channels 3 arerpartly cut away to provide openings for the electrodes 19. Each electrode 19 comprises a copper block 20 provided vvith a. graphite contact or face piece 21. These electrodes are guided in openings in the metal plate 22 and insulating plate 23 carried upon the blocks 24 bolted to the Webs 18. To operate the electrodes 19 an operatingrod 25 is pivotally connected at one end to a clip 66 secured tobut insulated from the copper block 20. At its other end the rod 25 has a pin and slot connection toy an operating lever 26 that is pivotally vsupported at one end on a bracket 27 carried by a side member 7 of thetruck. To the other end of thelever 26, a foot pedal 28 is pivotally connected. Surrounding the rods 25 are springs 39 confined between the Washers 40 secured on the rods 25 and the U-shaped straps 41 which are secured to the flanges 13 of the channels 3 and are provided with openings through which the rods 25 pass. V

The block 2() of the electrode 19 is provided with an opening in which the insulation 29 is held by a metal plate 30 secured to theblock by screws (not shown). Secured `in position by the insulation 29 and plate 30 is a nut 31 on the threaded stem 32 of the clip 6,6, the stem 32 being insulated from the plate 30 by the bushing 33.

At its other end, the web 18 ofthe channel is slotted toprovide openings for the operating levers 34 which are pivoted at` 35 to brackets 36 carried by an end member 4. To the lovver end of the levers 34 are attached cables 37VWhichl pass over pulleys 38, carried by 'the member' 4 at the opposite end of the car, and are connected to the lever 26. To this end of the lever 34 there is also secured an operating arm 42 having a pedal 43 pivotally connected to its other end. The other ends of the levers 34 are forked, as at 44, so as to surround the operating rods 45 and engage the collars 46 secured to the rods 45. The rods 45 are connected at one end to the electrodes 47, the connection being as shown in Fig. 5, and have their other ends guided in openings in angle bar members 48 attached to the`websv secured to the channels 3 by the bolts 56 that secure the plates 52 and 53 and blocks 54 in place.

In the pit 12 are placed the transformers, one for each chamber 2, having, as shown diagrammatically in Fig. l, a primary coil connected to a suitable source of power (not shown) and a secondary coil 58 connected through a suitable control device, as switch 60, to flexible conductors 62 that con neet the terminals of the secondary coil to the electrodes 19 and 47.

In the operation of our device, the electrode 47 is retracted against the action of spring 49 by the operation of the arm 42 permitting the insertion of the rod 63 into the chamber 2, the rod 63 being inserted until it engages with the electrode 19 and subsequently held in suehengagement by the pressure exerted by the electrode 47 under the action ot' spring' 49. As the current is passed through the rod 63 and it is heated, the spring 49 permits the retraction ot' the electrode 47 duriiig the expansion of the rod 63 but keeps both electrodes bearing against the rod so as to insure proper contact. Movement of the truck back and forth is permitted by the flexible conductors 62 so that all chambers 2v may be loaded. 'When a rod 63 has been heated, the truck is moved so that the rod may be fed from the heating chamber to the machine that is to operate upon the heated rod. The lever 26 is then operated and, during the rst part of its movement, it operates the lever 34 to operate the electrode 47 and thus remove the pressure from the rod 63. The pin and. slot connection between the lever 26 and the rod 25 leaves the electrode 19 in position during this movement ot the lever 26, butupon a slight retraction of the electrode 47 the pinY engages the bottom of the slot and the electrode 19 is thereafter withdrawn, `to the position shown in Fig. 4, simultaneously with the retraction of the electrode 47. Upon withdrawal of the rod 63 and release of the lever 26, the spring 39 returns the electrode 19 to its normal position, as shown in Fig. l, and the spring 49 returns the electrode 47 and lever 34 to normal position.

The lever 34 and electrode 47 may then be operated to permit of another rod being inserted in the chamber.

`What we claim is:

l. ln an electric heater, a heat retaining structure having a Vchamber to receive the work piece and a plurality of operable elec trodes positioned at the ends oi' said chamber to engage the work piece and means 'for initiating the operation of said electrodes in succession, one of said electrodes being adapted to be yshifted by the expansion of the work piece.

2. In an electric heater, a heat retaining structure having a chamber to receive the work, a vertically movable electrode adapted to serve as a stop upon the insertion of the work piece and a horizontally movable electrode adapted to be shifted by the expansion of the work piece. l 1

3. ln an electric heater, a secondary coil having an electrode at each end of said coil, means whereby one ot said electrodes may be operated independently and means whereby the other of said electrodes be operated automatically following the initiating of the operation ofthe iirst electrode.

` 4. In an electric heater, a heat retaining structure having a chamber adapted to receive a work piece, a plurality of' electrodes adapted to be positioned at the ends ot said chamber to engage the work piece and means whereby one of said electrodes may be operated independently of and in conjunction with the other ot said electrodes.`

5. ln an electric heater, a heat retaining structure having a chamber adaptedto receive the work piece, movable electrodes adapted to engage the ends of thework piece, means to operate one of said electrodes to permit of the insertion ot the work piece into the chamber and means to discngage both of said electrodes from the workpiece to permit of the withdrawal ot' the work piece from the chambers 6. ln an electric heater, a. plurality o'l' electrodes, means to operate one of said electrodes independently of the'other and means to operate said electrodes together, said last named operating means initiating the operation o one oi said electrodes in advance of the operation or" the otherelectrodc.

7. In an electric heater, a heat retaining structure having a chamber adapted to receive the work piece, electrodes at the ends of said chamber adapted to engage the Work piece and means for operating one of said electrodes from either end of said chamber.

8. In an electric heater, a heat retaining structure having a chamber adapted to receive the Work piece, electrodes at the ends of said chamber adapted to engage the Work piece, levers adapted to operate said electrodes and a means operatively connecting one of said levers to the other lever.

9. In an electric heater, a heat retaining structure having a chamber adapted to receive the Work piece, an electrode adapted to be positioned in front of said chamber to form a stop for the Work piece and operating means for said electrode adapted to move said electrode from in front of said chamber.

10. In an electric heater, a heat retaining structure having a chamber to receive the Work piece, electrodes adapted to engage the work piece, one of said electrodes being adapted to be shifted by the expansion of the Work piece, and means operating said electrodes in different directions to disengage said electrodes from the Work piece.

11. In an electric heater, a heat retaining structure having a chamber to receive the Work piece, an electrode at each end of said chamber, means to operate one of said electrodes to permit the Work piece to be inserted at one end of said chamber and means to disengage both of said electrodes from said Work piece to permit Withdrawal of the work piece from the other end of said chamber.

12. In an electric heater, an electrode at each end of said heater, one electrode being operable from one end of the heater and both electrodes being operable from the other end of said heater.

13. In an electric heater, electrodes at opposite ends of said heater and operating means adapted to initiate the operation ot' an electrode at one end of the heater in advance of the operation of an electrode at the other end of the heater.

141-. In an electric heater, a box like structure ot heat insulating material, heat insulating Walls dividing said structure into a plurality of heating chambers open at the ends and a Work-engaging electrode at each open end of each chamber.

15. In an electric heater, movable electrode, a vertically movable electrode, means to operate the horizontally movable electrode to permit insertion of the Work piece and means to automatically operate the vertically movable electrode following the initiation of the operation oi the horizontally movable electrode to permit the removal of the work piece.

a horizontally 16. In an electric heater having a heating chamber for long bars and a heating circuit adapted to be completed by a bar in said chamber, said chamber being adapted for maintaining the bar in a heated condition upon interruption of said heating circuit and said circuit comprising electrodes operated in different directions to release the bar.

17. In an apparatus of the class described, a heater provided With a heating chamber, relatively movable electrodes located outside of and beyond the ends of said chamber and means initiating the operation of Said electrodes in succession.

18. In an electric heater, a heating chamber for a long bar, a heating circuit comprising relatively movable electrodes located outside of and beyond the ends of said chamber for engaging the ends of the bar and means operating said electrodes in different directions, said chamber being so constructed as to maintain the bar in a heated condition upon the breaking of said circuit.

19. In an electric heater, a heating chamber for a long bar, an electrode located at one end of said chamber and means at each end of said chamber for moving said electrode toward and away from one end of said bar, said chamber being so constructed as to maintain said bar in a heated condition upon movement of said electrode from said bar.

20. In an electric heater, a heating chamber for a long bar, an electric circuit for .heating the bar having electrodes located outside of said chamber and means operating said electrodes in different directions, said chamberbeing constructed so as to be heated by the bar and delay the cooling of the bar upon the breaking of said circuit.

21. In an electric heater, a heating cham4 ber for a long bar, said bar projecting beyond one end of said chamber, an electrode for engaging the projecting end of said bar and means at each end4 of said chamber for moving said electrode toward and away from the projecting end of said bar.

22. In an apparatus of the class described, a heater provided with a heating chamber, relatively movable work contacting electrodes located outside of and beyond the opposite ends of said chamber, and means for operating said electrodes to move the same to engage them with or disengage them from the Work.

In Witness whereof We have hereunto set our hands.

VILLIAM S. JOHNSON. JOHN W. SHEFFER. 

